It is well-known that toilet seats can be a source of disputes in the home where men, after using the toilet as a urinal, leave the seat in the "up" position, which can anger women who must lower the seat before using the toilet. Even worse, a person inattentive to the seat's position might accidentally sit upon the bowl while the seat is up and injure himself. Finally, when the seat is left up, household pets have easy access to the water in the bowl and will frequently drink from it.
Many attempts have been made to alleviate these problems by automating the seat-closing function. However, many of the devices in this field consist of unattractive mechanisms, cords, or levers attached to the exterior of the toilet, or require installation of plumbing or mechanical elements inside the toilet tank behind the bowl. Some prior toilet seat closing mechanisms have employed electric motors which of course are dangerous to use near water.
Some recent toilet seat closing devices have managed to eliminate mechanisms visible on the exterior of the toilet, but have suffered from certain drawbacks. U.S. Pat. No. 5,279,000 to Mercier et al., and No. 5,388,281 to Wiklund et al., both disclose a seat closure mechanism which is self-contained within the seat hinge on the toilet. Both devices employ a hydraulic cylinder or dashpot to slow the descent of the seat to the bowl. The closing device in the Wiklund patent uses a coil spring to bias the seat toward the closed position and start the closing motion, whereas the Mercier device uses stops mounted on the seat hinge to prevent the seat from being raised to the full 90.degree. vertical position (stopping the seat a few degrees short), thus relying on gravity to pull the seat into motion after it is raised. Thus, the devices disclosed in the Wiklund and Mercier patents allow the seat to move slowly when it is in a vertical or near-vertical orientation, and then somewhat faster as the seat falls and the center of gravity moves laterally farther away from the hinge. However, both of these devices lack a means for adjusting the descent speed separately from the initial delay time. This arrangement makes a long delay phase (the period of slow seat motion during which the seat is sufficiently open to allow use of the toilet for urination) incompatible with a rapid descent speed. If the user "tightens" the dampening means to increase the time available to use the toilet, he necessarily slows the seat's descent over the entire range of motion, and any attempt to increase the descent speed will reduce the time available to use the toilet.
U.S. Pat. No. 5,153,946 to Yoke et al. discloses a toilet seat closing mechanism which employs a hydraulic dampener to slow the descent of the seat and a timer to adjust the delay time without affecting the descent speed. However, in this device the descent speed is not adjustable at all, which can make the device difficult to adapt for use with a toilet seat that is extremely light or heavy, or difficult to simply tune its functioning according to the user's preference. The closer is also mechanically complex, requiring two separate hydraulic chambers for regulating delay time and descent speed. Furthermore, in the preferred embodiment, the device requires substantial modification of the toilet seat to include mechanical elements for interrupting the progress of the timer under certain conditions.
Therefore, a need exists for a self-contained, compact toilet seat closing device which has a very slow initial rate of descent, providing a time delay, and a controlled final descent speed, each separately adjustable by the user, which is easily installed on a standard toilet with no addition of mechanical elements inside the tank or on the sides of the toilet, and which is as mechanically simple as possible.
It is an object of the present invention to provide an improved device for automatically closing a toilet seat after use.
It is a further object of the present invention to provide such a closing device which effectively delays the main closing action for a period easily adjustable by the user, and then closes the seat at a speed easily adjustable by the user separately from the delay duration adjustment.
It is yet a further object of the present invention to provide a closing device which is easily installed on a standard flush toilet with little or no modification to, and no installation of mechanical elements in, the toilet tank, plumbing, seat, or lid.
It is yet a further object of the present invention to provide a closing device which is compact with an unobtrusive, aesthetically pleasing appearance.
It is yet a further object of this invention to provide a closing device with the above-recited virtues which is as mechanically simple as possible.